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    <title>Document</title>
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<body>
    <div id="this">123</div>
    <script>
        // function fn (a, b) {
        //     return a + b
        // }
        // const fn1 = (a, b) => a + b
        // const fn2 = a => ({ a: a })
        const thisDiv = document.querySelector('#this')
        // const fn3 = () => {
        //     // console.log(arguments);
        //     console.log(this);
        // }
        // fn3()
        // console.log(fn3.prototype);
        // thisDiv.addEventListener('click', () => {
        //     console.log(this);
        // })
        var uname = 'ls'

        const obj = {
            uname: 'zs',
            age: 18,
            sayHi: function () {
                let uname = 'harry'
                const fn = () => {
                    console.log(uname);
                }
                fn()
            }
        }
        obj.sayHi()
    </script>
</body>

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